Cable opens fire on Cameron

The Lib Dems may have been in an assertive mood recently, but Vince Cable's attack on David Cameron's immigration speech is still remarkable. The Business Secretary described the Prime Minister's comments as "very unwise" and said the speech "risked inflaming extremism". It's one of the most striking acts of disloyalty from a cabinet minister in recent history. One suspects that, were this a single-party government, Cable would be facing the sack. In the age of coalition government, however, the rules of the game have changed.

After all, this isn't the first time that the Business Secretary has attacked Cameron's stance on this issue. Last September he said the immigration cap was "doing great damage" and admitted that he was "at the limit of collective responsibility". Given that the Lib Dems went into the general election promising an amnesty for illegal immigrants and ended up supporting the Tories' unworkable cap, it's hardly surprising that Cable feels the need to reassert his liberal credentials.

But while it's one thing for Cable to distance himself from the Conservative pledge to reduce net migration to "tens of thousands" a year (a policy that did not make it into the Coalition Agreement), it's quite another for him effectively to accuse the Prime Minister of pandering to racists. Yet the early indications are that he will keep his job: as one No 10 source simply told PoliticsHome, "Vince is Vince". But such a sanguine response won't go down well with the Tories, many of whom were frustrated that Cable remained in place after declaring "war" on Rupert Murdoch. They will rightly argue that a Conservative cabinet minister wouldn't receive such lenient treatment. Not for the first time, Cameron will be accused of weakness by his own side.